BACKGROUND
[0001] This disclosure relates generally to die cast components and, more particularly,
to a die casting system for casting a portion of a hybrid component.
[0002] Die casting involves injecting molten metal directly into a reusable die. Die casting
has typically been used to produce components that do not require high thermal mechanical
performance. For example, die casting is commonly used to produce components made
from relatively low melting temperature materials that are not exposed to extreme
temperatures. Die casting is particularly useful for producing parts having intricate
geometries.
[0003] Gas turbine engines include multiple components that are subjected to extreme temperatures
during operation. For example, the compressor section and turbine section of the gas
turbine engine each include blades and vanes having portions that are subjected to
relatively extreme temperatures. The blades and vanes are made of specialized materials
have been developed to withstand these temperatures. These materials can be costly
and heavy.
SUMMARY
[0004] An example die casting system includes a die that defines a cavity having a first
section and a second section. The first section is configured to receive a first portion
of a component. The second section is configured to receive a molten material. The
die holds the molten material as the molten material solidifies to form a second portion
of the component.
[0005] An example component has a first portion and a second portion. The first portion
comprises a first material. The second portion comprises a second material that is
different than the first material. The first portion, the second portion, or both
are die cast within a die. The first portion is secured to the second portion within
the die.
[0006] An example method of forming a turbomachine component includes holding a first portion
of a component within a first section of a cavity and die casting a second portion
of the component within a second section of the cavity. The first portion comprises
a first material and the second portion comprises a second material that is different
than the first material.
[0007] The various features and advantages of this disclosure will become apparent to those
skilled in the art from the following detailed description. The drawings that accompany
the detailed description can be briefly described as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008]
Figure 1 shows an example hybrid component.
Figure 2 shows an example die used to cast at least a portion of the Figure 1 hybrid
component.
Figure 3 shows an example portion of the Figure 1 hybrid component.
Figure 4 shows another example portion of another hybrid component.
Figure 4A shows yet another example portion of another hybrid component.
Figure 5 illustrates an example die casting system used to cast the Figure 1 hybrid
component.
Figure 6A illustrates the die casting system incorporating the Figure 2 die during
casting of a component.
Figure 6B illustrates the die casting system incorporating the Figure 2 die upon separation
from a die cast component.
DETAILED DESCRIPTION
[0009] Referring to Figures 1-3, a cavity 10 is established within an example die 14. A
first section 18 of the cavity 10 is configured to receive a first portion 22 of a
hybrid component 26. A second section 30 of the cavity 10 is configured to receive
a molten material, which solidifies within the cavity 10 to form a second portion
34 of the component 26.
[0010] The example component 26 is a blade assembly. The first portion 22 of the component
26 includes an airfoil 38 of the blade assembly. The second portion 34 of the component
26 includes a base 42, or shroud, of the blade assembly. Other examples include other
first portions and other second portions. Still other examples include more than two
portions.
[0011] In this example, the first portion 22 is investment cast and then placed within the
cavity 10. In another example, the first portion 22 is die cast in another cavity
that is different than the cavity 10. Still other examples may include die casting
a first portion within the cavity 10. The first portion 22 could also be a used component
that is bonded to a new second portion as part of a repair procedure.
[0012] A mechanical bond at an interface 44 secures the first portion 22 of the example
component 26 to the second portion 34. In this example, the molten material melts
an area 45 of the first portion 22 near the interface 44. The mechanical bond is then
formed as the area 45 of the first portion 22 solidifies within the second section
30 of the cavity 10 with the second section 30.
[0013] In this example, the material forming the first portion 22 is different than the
material forming the second portion 34. The example component 26 is considered a hybrid
component because the component 26 comprises more than one type of material.
[0014] In one example, the material forming the first portion 22 is a cobalt alloy, and
the material forming the second portion 34 is a nickel alloy. In another example,
the material forming the first portion 22 is a nickel alloy, and the material forming
the second portion 34 is a cobalt alloy. In another example, the material forming
the first portion 22 is a cobalt alloy of one composition, and the material forming
the second portion 34 is a cobalt alloy of a similar or different composition. In
another example, the material forming the first portion 22 is a nickel alloy, and
the material forming the second portion 34 is a similar or different nickel alloy.
In yet another example, the material forming the first portion 22 is a columnar or
single crystal cast directionally solidified material, and the material forming the
second portion 34 is a less dense nickel material. In yet another example, the material
forming the first portion 22 is a columnar or single crystal cast directionally solidified
material, and the material forming the second portion 34 is a cobalt material. The
materials selected may be adjusted depending on desired performance, cost, etc.
[0015] Referring now to Figure 4, in another example, a first portion 22a is secured relative
to a second portion (not shown) by their respective geometries. For example, the first
portion 22a may include extensions 46 each having an enlarged head 48. In such an
example, the molten material of the second portion flows around the extensions 46
as the molten material is moved into the second section 30 of the cavity 10. After
solidifying, the extensions 46, and their enlarged heads 48, prevent the first portion
22a from moving relative to the second portion.
[0016] Referring now to Figure 4A, another example first portion 22b includes a rail 47
configured to be slidably received within a groove 49 established in a second portion
34b. The second portion 34b could also be cast about the rail 47 rather than slidably
receiving the rail.
[0017] Referring now to Figure 5 with continued reference to Figure 1-2, a die casting system
50 includes the die 14 having a plurality of die elements 54, 56 that function to
cast the second portion 34 of the component 26. Although two die elements 54, 56 are
depicted, it should be understood that the die 14 could include more or fewer die
elements, as well as other parts and configurations.
[0018] The die 14 is assembled by positioning the die elements 54, 56 together and holding
the die elements 54, 56 at a desired positioning via a mechanism 58. The mechanism
58 could include a clamping mechanism of appropriate hydraulic, pneumatic, electromechanical
and/or other configurations. The mechanism 58 also separates the die elements 54,
56 subsequent to casting.
[0019] The die elements 54, 56 define internal surfaces 62 that cooperate to define a die
cavity 60 portion of the cavity 10. A shot tube 64 is in fluid communication with
the die cavity 60 via one or more ports 66 located in the die element 54, the die
element 56, or both.
[0020] A shot tube plunger 68 is received within the shot tube 64 and is moveable between
a retracted and injection position (in the direction of arrow A) within the shot tube
64 by a mechanism 80. The mechanism 80 could include a hydraulic assembly or other
suitable mechanism, including, but not limited to, pneumatic, electromechanical, or
any combination thereof.
[0021] The shot tube 64 is positioned to receive a molten metal from a melting unit 82,
such as a crucible, for example. The melting unit 82 may utilize any known technique
for melting an ingot of metallic material to prepare a molten motel for delivery to
the shot tube 64, including but not limited to, vacuum induction melting, electron
beam melting and induction skull melting. The molten metal is melted by the melting
unit 82 at a location that is separate from the shot tube 64 and the die cavity 60.
In this example, the melting unit 82 is positioned in close proximity to the shot
tube 64 to reduce the required transfer distance between the molten metal and the
shot tube 64.
[0022] The molten metal is transferred from the melting unit 82 to the shot tube 64 in a
known manner, such as pouring the molten metal into a pour hole 63 in the shot tube
64, for example. A sufficient amount of molten metal is poured into the shot tube
64 to fill the die cavity 60. The shot tube plunger 68 is actuated to inject the molten
metal under pressure from the shot tube 64 into the die cavity 60 to cast the component
26. Although the casting of a single portion of the component 26 is depicted, the
die casting system 50 could be configured to cast multiple components in a single
shot.
[0023] The example die casting system 50 depicted in Figure 5 is illustrative only and could
include more or less sections, parts and/or components. This disclosure extends to
all forms of die casting, including but not limited to, horizontal or vertical die
casting systems.
[0024] The example hybrid component 26 is a blade for a turbomachine, such as a turbine
blade for a turbine section of a gas turbine engine. However, this disclosure is not
limited to the casting of blades. For example, the example die casting system 50 of
this disclosure may be utilized to cast aeronautical components including blades,
vanes, combustor panels, blade outer air seals, or any other component where performance
associated with multiple materials is desired, including non-aeronautical components.
[0025] Figures 6A and 6B illustrate portions of the die casting system 50 during casting
(Figure 6A) and after the die elements 54, 56 separate (Figure 6B). After the molten
metal solidifies within the die cavity 60, the die elements 54, 56 are disassembled
relative to the component 26 by opening the die 14 via the mechanism 58.
[0026] Features of the disclosed examples include a hybrid component that is at least partially
die cast. Die casting a portion of the hybrid component is less expensive and faster
than investment casting the entire component. The hybrid component has a blade that
is a different material than its base, for example. Another feature is that materials
can be selected depending on the desired properties for particular areas of the component.
[0027] This same technique can be used to repair or replace a given die cast component.
That is, during an overhaul and repair process, the salvageable section of the hardware
can be removed and the locking feature can be machined into the retained segment.
The section of the component to be repaired can then be die cast onto the existing
segment as necessary.
[0028] The preceding description is exemplary rather than limiting in nature. Variations
and modifications to the disclosed examples may become apparent to those skilled in
the art that do not necessarily depart from the essence of this disclosure. Thus,
the scope of legal protection given to this disclosure can only be determined by studying
the following claims.
1. A die casting system (50), comprising:
a die (14) that defines a cavity (10) having a first section (18) and a second section
(30), the first section (18) configured to receive a first portion (22) of a component
(26), and the second section (30) configured to receive a molten material, wherein
the die (14) holds the molten material as the molten material solidifies to form a
second portion (34) of the component (26).
2. The die casting system of claim 1, wherein the component (26) is an aircraft component,
a gas turbine engine component, or a blade assembly.
3. The die casting system of claim 2, wherein the first section (18) forms at least a
blade portion (38) of the blade assembly, and the second section (30) forms at least
a shroud portion (42) of the blade assembly.
4. The die casting system of any preceding claim, wherein the first portion (22) of the
component (26) comprises a cobalt alloy, and, for example the second portion (34)
of the component (26) comprises a nickel alloy.
5. The die casting system of claim 4, wherein the first portion (22) of the component
(26) comprises a metal that is less dense than the second portion (24) of the component
(26).
6. The die casting system of any preceding claim, wherein the first section (22) is investment
cast.
7. The die casting system of any preceding claim, wherein the molten material held in
the second section (30) melts some of the first portion (22).
8. A component (26), comprising:
a component (26) having a first portion (22) and a second portion (34), the first
portion (22) comprising a first material and the second portion (34) comprising a
second material that is different than the first material, wherein at least one of
the first portion (22) or the second portion (34) are die cast within a die (14),
and first portion (22) is secured to the second portion (34) within the die (34).
9. The component of claim 8, wherein the first material is a cobalt alloy, and/or the
second material is a nickel alloy.
10. The component of claim 8 or 9, wherein the first portion (22) comprises an airfoil
(38) of a blade assembly, and/or the second portion (34) comprises a used shroud (42)
of a blade assembly.
11. The component of claim 8, wherein the first portion (22) is an airfoil (38) comprising
a columnar or single crystal configuration first material and the second portion (34)
is a shroud (42) comprising a nickel die cast second material, the shroud (42) less
dense than the airfoil (38).
12. The component of any of claims 8 to 11, wherein the first portion (22) is investment
cast.
13. A method of forming a turbomachine component (26), comprising
holding a first portion (22) of a component (26) within a first section (18) of a
cavity (10); and
die casting a second portion (34) of the component (26) within a second section (30)
of the cavity (10), wherein the first portion (22) comprises a first material and
the second portion (34) comprises a second material that is different than the first
material.
14. The method of claim 13, including melting a least some of the first material using
the second material.
15. The method of claim 13 or 14, including repairing the component (26) by securing a
new second portion (34) to a used first portion (22).